Hundal Bjørg Kristine, Lutfi Esmail, Sigholt Trygve, Rosenlund Grethe, Liland Nina Sylvia, Glencross Brett, Sissener Nini Hedberg
Department of Feed and Nutrition, Institute of Marine Research, P.O. Box 1870, Nordnes, 5817 Bergen, Norway.
Department of Nutrition and Feed Technology, Norwegian Institute of Food, Fisheries and Aquaculture Research (Nofima), P.O. Box 210, 1431 Ås, Norway.
Metabolites. 2022 Feb 8;12(2):159. doi: 10.3390/metabo12020159.
The present study aimed at elucidating the effects of graded levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the hepatic metabolic health of Atlantic salmon reared in sea cages. Diets containing 10, 13, 16 and 35 g/kg EPA + DHA (designated diets 1.0, 1.3, 1.6 and 3.5, respectively) were fed in triplicate through a full production cycle from an average starting weight of 275 g to slaughter size (~5 kg). Feeding low dietary EPA + DHA altered the hepatic energy metabolism, evidenced by reductions in tricarboxylic acid cycle intermediates originating from β-oxidation, which was compensated by elevated activity in alternative energy pathways (pentose phosphate pathway, branched chain amino acid catabolism and creatine metabolism). Increases in various acylcarnitines in the liver supported this and indicates issues with lipid metabolism (mitochondrial β-oxidation). Problems using lipids for energy in the lower EPA + DHA groups line up well with observed increases in liver lipids in these fish. It also aligns with the growth data, where fish fed the highest EPA + DHA grew better than the other groups. The study showed that diets 1.0 and 1.3 were insufficient for maintaining good liver metabolic health. However, diet 3.5 was significantly better than diet 1.6, indicating that diet 1.6 might also be suboptimal.
本研究旨在阐明不同水平的二十碳五烯酸（EPA）和二十二碳六烯酸（DHA）对网箱养殖大西洋鲑肝脏代谢健康的影响。分别含有10、13、16和35克/千克EPA + DHA的饲料（分别指定为饲料1.0、1.3、1.6和3.5），以一式三份的方式投喂，从平均初始体重275克开始，直至达到屠宰规格（约5千克）的整个生产周期。低水平的饲料EPA + DHA改变了肝脏能量代谢，这表现为源于β-氧化的三羧酸循环中间产物减少，而这通过替代能量途径（磷酸戊糖途径、支链氨基酸分解代谢和肌酸代谢）活性的升高得到补偿。肝脏中各种酰基肉碱的增加支持了这一点，并表明存在脂质代谢问题（线粒体β-氧化）。在较低EPA + DHA组中，利用脂质获取能量存在问题，这与这些鱼肝脏脂质的增加情况相符。这也与生长数据一致，即投喂最高EPA + DHA饲料的鱼比其他组生长得更好。该研究表明，饲料1.0和1.3不足以维持良好的肝脏代谢健康。然而，饲料3.5明显优于饲料1.6，表明饲料1.6可能也不是最优的。
